On a machine of this type shown and described in patent application No. DE-A-28 33 814, the rotor is jointed in relation to the support beam through two joints provided above one another. One of the two joints comprises horizontal pivot pins which are connected to the rotor, while the other one of the two joints comprises a vertical pivot pin connected to the support beam. The two joints are intended to allow the rotor to follow the irregularities of the ground and to adapt to the curves of the path over which the machine is moved.
The ability of this machine to adapt to the curves of the path is, however, very limited. The rotor of the machine actually can be moved only by an angle of slight value around the vertical pivot pin if it is desired to provide it with a drive in correct rotation from the tractor. This machine is, therefore, not able to provide a good windrowing under all conditions.